VDOT Air Conditioning (A/C) System Diagnosis. Oldsmobile Intrigue 1998

For 1990-2009 cars only

Makes 🢒 Oldsmobile 🢒 1998 🢒 Intrigue 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 VDOT Air Conditioning (A/C) System Diagnosis

The purpose of the symptom diagnostic procedures is to diagnose the following components for any problems that may cause insufficient cooling:

•	The V5 compressor

•	The VDOT refrigerant system

The V5 Compressor is a variable displacement compressor. The V5 compressor responds to the air conditioning demands by changing the stroke rather that cycling the clutch. A control valve is located in the rear head of the A/C compressor. The control valve completes the following functions; senses the compressor low side pressure and causes the compressor mechanism to stroke. The V5 compressor always runs and the system does not cycle. These diagnostic procedures differ from those used for fixed displacement systems. Use the symptom diagnostic procedures in order to avoid unnecessary replacement of any A/C components.

The A/C system is operating properly if the discharge air temperature and compressor pressures are equal to those in the System Performance Test (Table) .

Preliminary Checks

Inspect the A/C fuse, replace as necessary.
Inspect the A/C blower operation, repair as necessary.
Inspect the clutch coil electrical connection, repair as necessary.
Check for diagnostic codes, repair as necessary.
Inspect the drive belt, replace the drive belt if it is damaged.
Inspect the operation of the electric cooling fans, repair as necessary.
Inspect the condenser for restricted air flow, clean as necessary.
Inspect the system for any restrictions in the air flow.

Low Side and High Side Pressures

Step	Action	Value(s)	Yes	No
1	Were you sent here from the System Performance Test?	--	Go to Step 2	Go to System Performance Test (Table)
2	The ambient air temperature must be at least 16° C (60° F) place the ignition in the OFF position. Connect the A/C gauges. Are the high and low side pressures approximately equal to the value specified?	345 kPa (50 psi)	Go to Step 7	Go to Step 3
3	Add 0.45 kg (1 lb of R-134a) Inspect the A/C system for leaks. Refer to Leak Testing . Is there a leak?	--	Go to Step 5	Go to Step 4
4	Are the high and low side pressures within the specified range?	207--345 kPa (30--50 psi)	System OK	Go to Step 5
5	Repair the leak. Is the repair complete?	--	Go to Step 6	--
6	Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging . Are the high and low side pressures above the value specified?	345 kPa (50 psi)	System OK	Go to Step 7
7	Let the engine run at idle speed. Set the A/C control assembly in the UPPER mode. Set the blower motor speed to high. Set the temperature to full cold. Push the A/C button to turn the A/C on. Does the clutch engage?	--	Go to Step 8	Go to Step 16
8	Check for noise coming from the compressor or the A/C drive belt area. Is the noise coming from the compressor or the belt?	--	Go to Step 9	Go to Step 19
9	Inspect the belt for slippage. Is the noise due to belt slippage?	--	Go to Step 10	Go to Step 11
10	Replace the accessory drive belt. Refer to Drive Belt Replacement in Engine Mechanical. Is the repair complete?	--	System OK	Go to Step 14
11	Listen to the A/C compressor for the noise. Is the noise coming from the A/C compressor?	--	Go to Step 12	Go to Step 14
12	Check the A/C lines for contact with other components. Is there contact with other components?	--	Go to Step 13	Go to Step 14
13	Reposition or replace the A/C lines as necessary. Is the repair complete?	--	System OK	Go to Step 19
14	Is the noise coming from the A/C compressor?	--	Go to Step 15	Go to Step 19
15	Replace the A/C compressor. Refer to Compressor Replacement . Is the noise still present?	--	Go to Step 19	System OK
16	Turn the ignition to the OFF position. Disconnect the electrical connector at the A/C compressor clutch. Connect a jumper wire from ground to one of the compressor clutch terminals. Connect a fused-jumper wire from the positive battery post to the other compressor clutch terminal. Does the clutch engage?	--	Go to Step 17	Go to Step 18
17	Repair the electrical circuit to the A/C compressor clutch. Run the engine at idle speed. Set the A/C control assembly in the A/C mode. Set the blower motor speed to high. Set the temperature control to full cold. Does the clutch engage?	--	System OK	Go to Step 19
18	Replace the A/C clutch coil. Refer to Compressor Clutch Coil Removal (V5 - Conventional Mount) . Is the repair complete?	--	System OK	Go to Step 19
19	Close all the windows and doors. Set the A/C control assembly in the UPPER mode. Set the blower motor to high. Set the temperature to full cold. Let the engine run at idle speed for 5 minutes. Feel the liquid line on both sides of the expansion (orifice) tube. Push the A/C button to the turn the A/C on. Is the temperature the same on both sides of the expansion (orifice) tube?	--	Go to Step 20	Go to Step 25
20	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Inspect for a missing expansion (orifice) tube or O-ring. Is the expansion (orifice) tube or O-ring missing?	--	Go to Step 21	Go to Step 22
21	Replace the missing expansion (orifice) tube or O-ring. Refer to Expansion (Orifice) Tube Replacement . Is the repair complete?	--	Go to Step 23	--
22	Inspect for a restricting in the high side line; visually check the line/pipe for a frosty spot or physically check the line/pipe for a temperature difference to locate the restriction. Is there a restriction?	--	Go to Step 24	--
23	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Leak test the system. Refer to Leak Testing . Check the air outlet discharge temperature. Refer to System Performance Test (Table) . Is the air outlet discharge temperature within specifications?	--	System OK	Go to Step 25
24	Repair the restriction in the high side line. Is the repair done?	--	System OK	--
25	Operate the A/C system for 5 minutes or longer. Record the low and high side pressures with the electric cooling fans ON. Locate the restriction of the low and high side pressures. Refer to Low Side and High Side Pressure Chart . Do the low and high side pressures intersect on the right side of the table?	--	Go to Step 26	Go to Step 36
26	Set the A/C control assembly in the UPPER mode. Set the blower motor to high. Set the temperature to full cold. Let the engine run at idle speed for 5 minutes. Feel the liquid line on both sides of the expansion (orifice) tube. Push the A/C button to the turn the A/C ON. Feel the liquid line between the condenser and the expansion tube. Is the liquid line cold?	--	Go to Step 27	Go to Step 31
27	Check the cooling fan(s). Are the fans operating?	--	Go to Step 28	Go to Step 29
28	Check the air flow at the condenser for restrictions. Is the air flow restricted?	--	Go to Step 30	Go to System Performance Test (Table)
29	Repair the cooling fan(s) as necessary. Is the repair complete?	--	System OK	--
30	Remove the restriction. Is the repair complete?	--	System OK	--
31	Check the A/C system for an overcharge of refrigerant. Is the A/C system overcharged?	--	Go to Step 32	Go to Step 33
32	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete?	--	System OK	Go to System Performance Test (Table)
33	Check for air in the A/C system. Is there a leak in the A/C system?	--	Go to Step 34	Go to System Performance Test (Table)
34	Leak test the A/C system. Refer to Leak Testing . Is there a leak in the A/C system?	--	Go to Step 35	Go to System Performance Test (Table)
35	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Repair the leak in the A/C system. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete?	--	System OK	--
36	With the engine running, connect the high and low side pressure gages. Are the high and low side pressures equal to the specified value?	207 kPa (30 psi)	Go to Step 37	Go to Step 42
37	Close all the vehicle doors and windows. Run the engine at 2000 RPM. Set the temperature control assembly to full cold. Set the blower motor speed to high. Cycle the modes from VENT to A/C every 20 seconds for 3 minutes. Are the high and low side pressures equal the specified value?	207 kPa (30 psi)	Go to Step 38	--
38	Inspect for the following conditions: A slow raise in pressure in both the low and high side gages. The compressor suction line is warm. The discharge line is very hot. Do all of the above conditions exist?	--	Go to Step 39	Go to Step 40
39	Replace the A/C compressor. Refer to Compressor Replacement . Is the repair complete?	--	System OK	--
40	Turn the engine OFF. With the compressor clutch disengaged, does the compressor clutch driver (not the pulley) turn freely by hand?	--	Go to Step 39	Go to Step 41
41	Inspect the low side pressure. Is there a rapid rise in the low side pressure with the engine RPM between the value(s) shown?	2000--2800 RPM	Go to Step 52	Go to Step 39
42	Inspect the low side pressure. Is the low side pressure within the specified values?	172 --241 kPa (27--38 psi)	Go to Step 43	Go to Step 52
43	Feel the liquid line before the expansion (orifice) tube. Is the line cold?	--	Go to Step 44	Go to Step 46
44	Inspect the liquid line for a restriction before the expansion (orifice) tube. Is there a restriction the liquid line before the expansion (orifice) tube?	--	Go to Step 45	Go to System Performance Test (Table)
45	Repair the restriction or replace the liquid line before the expansion (orifice) tube. Is the repair complete?	--	System OK	Go to System Performance Test (Table)
46	Add 0.5 kg (1 lb) of R-134a refrigerant to the system. Does the cooling improve?	--	Go to Step 47	Go to Step 49
47	Preform a leak test. Refer to Leak Testing . Is there a leak?	--	Go to Step 48	System OK
48	Repair the leak. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete?	--	System OK	--
49	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Inspect the expansion (orifice) tube. Is the expansion (orifice) tube plugged?	--	Go to Step 50	--
50	Remove and clean or replace the expansion (orifice) tube. Refer to Expansion (Orifice) Tube Replacement . Is the repair complete?	--	Go to Step 51	--
51	Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete?	--	System OK	Go to System Performance Test (Table)
52	Connect the high and low side gages. Close all the vehicle doors and windows. Run the engine at 2000 RPM for 5 minutes. Set the A/C control assembly to the UPPER mode. Set the temperature control to full cold. Push the A/C button to turn on the A/C on. Set the blower motor speed on low. Is the low side pressure within the value (s) shown?	172--241 kPa (25--35 psi)	Go to System Performance Test (Table)	Go to Step 53
53	Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Replace the control valve. Refer to Compressor Control Valve Assembly Install (V5 - Conventional Mount) in Automatic Control Air Conditioning. Is the repair complete?	--	Go to Step 54	--
54	Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete?	--	System OK	Go to System Performance Test (Table)